Abstract:Based on a case study of underground projects at a power station in Shanghai area,the researches on the dynamic characteristics of liquefiable sandy silt are conducted by means of dynamic triaxial tests with a consideration of such influencing factors on liquefaction as cyclic stress,consolidation pressure,structure,particle composition and parameters for liquefaction evaluation are obtained.The seed simplified method is adopted to verify the results of the laboratory method.Some scientific conclusions on earthquake resistant design of this project are proposed and can be referred to the similar engineering projects of ground improvement for liquefaction mitigation.